- This topic has 14 replies, 3 voices, and was last updated 5 years, 12 months ago by
.
-
Posts
-
Hi,
I am trying to calibrate and profile a laptop display with Displaycal. The trouble is that red colors appear way too saturated after calibration/profiling (in color managed apps like PS). What is the problem and how can I fix this?
My laptop is an Acer Apsire V 3-372. According to Displaycal it can show about 70% sRGB. Measurement device is a Spyder 5. Lightness of the display is at 100%. Settings of Displaycal are the default settings, but I have also tried sRGB and profile type curves. Result is always the same. Oversaturation of reds also occurs when I calibrate with Spyder Express.
When I viewthe same photos (e.g. of a red flower) on external (calibrated or unclibrated) displays or a tablet or a phone, saturation is normal.
I guess the problem has something to do with the fact that my laptop’s color space is quite small, i.e. the oversaturated colors are colors that the display actually cannot show. And/or rendering intents, but I don’t know how that works.Otherwise the calibration seems ok, the other colors are slightly more saturated than without color management.
Thanks in advance
b
I am trying to calibrate and profile a laptop display with Displaycal. The trouble is that red colors appear way too saturated after calibration/profiling (in color managed apps like PS). What is the problem and how can I fix this?
The problem with many laptop displays is that they have a small gamut which often covers only a fraction of the sRGB color space. This is especially true for this Acer laptop which according to reviews only covers around 50% of sRGB. So, saturated sRGB colors get clipped to the nearest in-gamut color, leading to loss of detail. It is not possible though to enlarge the gamut of your laptop display, as that is a hardware limitation.
The only way around this is to compromise by sacrificing accuracy for detail preservation in saturated colors, i.e. by creating a profile with a perceptual table that compresses (desaturates) the sRGB colors so they fit in the small display gamut. But not all applications can use the perceptual table of such a profile. The following steps show how to create such a profile (assuming you are using default settings):
- Enable advanced options in the “Options” menu.
- On the “Profiling” tab, click the small gear icon to bring up advanced gamut mapping options.
- Enable “Gamut mapping for perceptual intent”. The other options can be left as-is.
- Choose “Create profile from measurement data…” in the “File” menu and select your existing profile.
- Save the profile and install it after generation.
- In color managed applications, convert images to this display profile using perceptual intent.
Thank you for the answer. I tried your suggestion but it does not appear to work. When I convert to the new profile in PS, nothing happens, the colors do not change. The colors do change though if I just assign the profile (they are less saturated).
The situation is the same with GIMP and Affinity, but when I am converting, for the fraction of a second I see a less saturated image, then it switches back to saturated.
If I just assign the profile, the colors become less saturated if I assign the old profile, too.
And I want to mention another thing: I made the experience that Displaycal can really make look alike even displays that are very different. When I switch to dual screen and open the same image on both screens, they are surprizingly similar, even though one display is 60% sRGB and the other 100%. Most photos look extremely similar, the only exception are photos with a lot of bright red. In theory I could even use the laptop for editing photos. Photos that I edit on the laptop usually look ok (but never really great) on the external screen, too, but photos that I edit on the external screen might look oversaturated on the laptop.
I will try your suggestion again.
However, I am not quite sure which profile I am supposed to use (when converting), the old one or the new one?
Thank you for the answer. I tried your suggestion but it does not appear to work. When I convert to the new profile in PS, nothing happens, the colors do not change.
It’s important that you use perceptual intent for the conversion, and that the profile really is installed as display profile (otherwise there will be an implicit conversion to display).
The colors do change though if I just assign the profile (they are less saturated).
That’s the wrong thing to do: The profile describes your laptop display. If you assign it to (say) an sRGB immage, the image is interpreted as if it were in the display gamut, effectively disabling color management.
However, I am not quite sure which profile I am supposed to use (when converting), the old one or the new one?
The new one, and as mentioned above, it needs to be installed as display profile as well (this usually requires restarting applications that make use of the display profile so they pick up on the change).
Finally it worked. Turns out, I just forgot to switch to perceptual for the conversion.
However, I am wondering whether there is a way to create a profile which automatically does that very last conversion since many programs (e.g. image viewers) cannot convert to different profiles.
Also, the image that I converted has a screen profile if/when I save it. Is it possible to convert it back to sRGB so I can save it in sRGB?
Actually I just found out that there is one program which automatically displays the photos “correctly” (reds less saturated) without the additional “manual” conversion (with the new profile): Photoline.
Edit: another programs which supports the perceptual data in this kind of profile out of the box is IrfanView. Most other programs can be made to use the profile correctly by switching the rendering intent in the color management settings to “perceptual”. So far I see 3 exceptions: XnView, Affinity and Photoshop. There are no settings for rendering intent in XnView. In Affinity there are settings for rendering intent but they do not seem to work in this case, in addition, it is not possible to choose rendering intent when converting to a profile. Photoshop is similar, but fortuanately conversion works properly.
All in all, I think this solution works well. Thanks again for the help. Affinity and PS seem to be “buggy” in this respect.
Also, the image that I converted has a screen profile if/when I save it.
You should not save or edit the converted image, as it is only for preview on this specific laptop monitor after conversion. If your photo editor supports it, use a custom softproof instead.
there is one program which automatically displays the photos “correctly” (reds less saturated) without the additional “manual” conversion
Some programs will use the “default” rendering intent set in the profile (usually colorimetric, but in case of DisplayCAL LUT profiles, perceptual). Most ignore it though. Some others let you configure the rendering intent for display (GIMP). Some always render to display in a specific way (e.g. Photoshop, which always uses relative colorimetric with black point compensation unless you configure a custom softproof with the display profile as target).
Edit: another programs which supports the perceptual data in this kind of profile out of the box is IrfanView.
I have looked at IrfanView many times in the past and I cannot vouch for its color management. It either doesn’t seem to work or seems to ignore the display profile.
Most other programs can be made to use the profile correctly by switching the rendering intent in the color management settings to “perceptual”
That usually sets the default rendering intent for conversions, not the rendering intent used for display though (GIMP being a notable exception).
Well sometimes IrfanView works and somtimes it does not. At least that is my experience. It might also depend on the version. Previously I had a portable installation form portableapps.com which appeared to be less reliable. If color managment in IrfanView fails, it must be manually deactivated and reactivated. However, this time I did an entirely new “installation” from the zip-package form the Irfanview website and it seems to be reliable.
XnView, on the other hand, cannot deal with this particular profile properly. But it has other advantages such as showing EXIF in PNGs etc.
Are there even similar programs for Windwos that are Open Source? I only know of XnView and IrfanView.
What I also wanted to mention though: They are using IrfanView at the Staatliche Museen Berlin.Well if the color management does not work at all the IrfanView plugins might not be installed, but I thought you knew this. Without plugins it definitely does not work.
XnView, on the other hand, cannot deal with this particular profile properly.
Can you explain? XnView (like IrfanView with plugins) uses littleCMS, which is a fully ICC compliant color management module.
Well if the color management does not work at all the IrfanView plugins might not be installed
I haven’t looked at it in a while, so maybe that has been fixed. The current version (4.51) seems to work fine, and in fact, it has a few advantages over XnView, namely better support for greater than 8 bits per pixel images (XnView seemingly down-converts to 8-bit for display with inferior quality, which can lead to banding).
Basically color management works in XnView, but the program cannot use the perceptual data of this profile, i.e. the reds are oversaturated like in Photoshop and Affinity. BPC ist different too (darker). Photoline color managment also works with LCMS and everything is perfect. The only thing I can think of is that XnView uses a different (older?) version of LCMS, but I am not a programmer.
Basically color management works in XnView, but the program cannot use the perceptual data of this profile
I can’t reproduce this. In XnView’s options, have you set rendering intent to perceptual, enabled sRGB for untagged images, and made sure to set the correct display profile?
Note that XnView only color manages JPEG, PNG and TIFF images.
I used the the test images from here in IrfanView 4.51 and color management works for JPEG and TIFF, but not for PNG.
